This study is assessing the impact of timing of PD assessments on measures of platelet reactivity in patients undergoing PCI treated with cangrelor.

Cangrelor is characterized by reversible binding to the P2Y12 receptor and is promptly inactivated through dephosphorylation by ectonucleotidase leading to its very short plasma half-life. Consequently the timing at which PD assessments are performed after blood sample collection may impact measures of platelet reactivity in patients treated with cangrelor. We therefore hypothesize that measures of platelet inhibitory effects observed in cangrelor treated patients will reduce with time following blood sampling.

Inclusion Criteria:

• Age > 18 years old
• CAD patients (stable CAD, NSTE-ACS, or STEMI) undergoing PCI and treated with cangrelor per standard of care.
• Treated with aspirin prior to the PCI procedure per standard of care

Exclusion Criteria:

• Treatment with an oral P2Y12 inhibitor (clopidogrel, prasugrel or ticagrelor) within past 10 days
• Treatment with oral anticoagulation (vitamin K antagonist, dabigatran, apixaban, rivaroxiban) within past 3 days
• Treatment with a glycoprotein IIb/IIIa inhibitor during PCI
• Fibrinolytics within 48 hours
• Known hemoglobin<10 gm/dL
• Known platelet count <80x106/mL
• Active bleeding or hemodynamic instability
• Known end stage renal disease on hemodialysis
• Known severe hepatic dysfunction

Patients who are undergoing percutaneous coronary intervention (PCI) and have been treated with cangrelor per standard of care.